Didn't see Weller in the trailer. But the whole, 'You think the world is safe' voice over makes me think this is about a xenophobic plot to show how Earth would be safer if it didn't go into space, (hence the destruction of the starfleet), and pursued an isolationist policy. What's CB getting vengeance for? I still think it could be linked in with Weller, maybe a family connection. Or, just putting it out there again, Weller went and found Khan, or engineered his own super humans to keep 'earth for the earthlings (lol)'.
You may find that having is not so pleasing a thing as wanting. This is not logical, but it is often true." Spock (Amok Time)